In a broadband wireless communication system, a user terminal accesses an Internet Protocol (IP) network for a service by connecting to a base station over a radio channel. The base station has a fixed coverage. This coverage is determined by transmit powers of the base station and the terminal and, accordingly, is physically limited. Hence, the broadband wireless communication system is constructed to deploy a plurality of the base stations at proper intervals by taking into account the coverage of the base stations.
The terminal accesses the base station with the best channel among the base stations at the current location. The base station with the best channel can change according to the movement of the terminal. When this happens, it is advantageous for the terminal to alter its serving base station. When the change of the serving base station interrupts the service, the service quality is degraded. Thus, the broadband wireless communication system supports inter-cell handover to support the mobility of the terminal.
Optimization of the handover performance aims at providing the seamless service in the change of the serving base station and minimizing overhead of the signaling for the handover. Specific solutions and issues for optimizing the handover performance should be deliberated from various angles based on the characteristics of the system. To enhance the service quality, it is necessary to suggest a specific method for optimizing the handover performance in accordance with the characteristics of the system.